Find Volume of Revolution by Integrating 1/sqroot(3x+2) around x=0 and x=2

AI Thread Summary
To find the volume of revolution for the function y = 1/sqrt(3x+2) around the x-axis from x=0 to x=2, the relevant formula is V = π∫(y^2)dx. The integral simplifies to π∫(1/(3x+2))dx. A suggested method for integration involves using the substitution u = 3x + 2, which helps in solving the integral. The discussion highlights the need for understanding the constant that appears with the natural logarithm during integration. Overall, the integration process requires careful substitution to simplify and solve correctly.
DeanBH
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so i have y = 1/sqroot(3x+2)

find volume when rotated around x, regions are x=2 and x=0



equation needed: V= integral Pi*y^2*dx

so.

i do intergral pi* (1/sqroot(3x+2))^2 * dx

so i get pi integral 1/(3x+2) dx

so how do i integrate 1/sqroot(3x+2) ?

can someone take me though it , because i know there's meant to be a constant near the ln, but i don't know how to find it.


thanks, sorry if it's explained bad
 
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Try putting u=3x+2
 
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